To identify environmental triggers of type 1 diabetes (T1D) we have screened genetic T1D risk so far in > 60,000 consecutive newborns at the JDRF Center for Prevention of Type 1 Diabetes in Finland (cities of Turku, Oulu and Tampere; 11,000 annual births) using HLA-DQ gene alleles that associate with risk to or protection from T1D. Those with increased genetic risk and their at-risk siblings are invited to follow-up (3- to 12-month intervals). At this writing, >8,000 high-risk children are in regular follow-up; the oldest children followed from birth are now >7.4 years of age. 474 children have developed ICA, the autoantibody used in the primary screening of follow-up samples, alone (~ 50 % of the children) or in combination with other autoantibodies (~50 %; ICA with IAA, GADA or IA-2A). 64 of the screened children have progressed to T1D; 45 of them were in tight follow-up. If a child becomes ICA positive, all four autoantibodies are measured in child's all collected and future samples, to determine the time of expected onset of the autoimmune attack and to follow disease progression. We collect demographic, medical and life event data. We offer here our huge data and sample banks for collaborative studies. The samples comprise DNA (blood spots) on filter paper and as frozen blood; serum drawn at each follow-up visit; and isolated white blood cells, living white blood cells, RNA from peripheral blood, selected blood cells and other tissues for RNA and other analyses, and stool samples at monthly intervals from children with high genetic risk. The approach is well accepted by the population, as >70% of the at-risk children remain in the follow-up at least for 7 years. The study infrastructure is firm and well-functioning at all three participating Clinical Centers. Large numbers of children represent different stages of T1D development, allowing rapid collection also of new types of samples according to need. Finland's record-high annual TID incidence of 50/100.000 children below the age of 15 years markedly increases cost-efficiency of the case finding. DIPP approach has already proven its value in exploring the role of environmental triggers in T1D development.